Abstract Detail

Phylogenomics

Nie, Zelong [1], Ma, Zhiyao [2], Johnson, Gabriel [3], Ren, Chen [4], Ickert-Bond, Stefanie [5], Zimmer, Elizabeth [6], Wen, Jun [7].

Phylogenomic discordance in the New World grapes suggests widespread introgressions as a driver for species diversifications.

Although the grape genus Vitis is the economically most important fruit crop as the source of grapes and wine, species relationships within the genus have been highly controversial and unclear, especially for the New World members from subgenus Vitis. Here, we employed the Hyb-Seq approach and obtained 230 enriched nuclear loci in combination with whole-chloroplast genome sequence data to clarify the complex species relationships of the New World species and explore the extent of cytonuclear introgressions in the New World grapes. The chloroplast results supported the New World subgenus Vitis as monophyletic while nuclear data strongly revealed a paraphyletic relationship of the group with the Eurasian lineage nested within it. Contrary to plastid results that V. californica is sister to the remaining New World species, the nuclear data suggest the non-monophyly of V. californica, with one population close to the European taxa and the other two deeply nested within the New World lineage. Furthermore, most species sampled with multiple individuals from North America are found to be monophyletic in the nuclear phylogeny, but not monophyletic and collapsed into different clades in the chloroplast tree. A high level of cytonuclear discordance is widespread within the New World grapes, in terms of the relationships from the backbone of the subgenus Vitis to different species and among individuals within species. Incomplete lineage sorting cannot explain these patterns in most cases and most of the observed discordance is better explained by cytoplasmic introgression instead. Overall, our study represents one of the most comprehensive tests of the drivers of cytonuclear discordance and highlights the potential network-like gene flows and hybridizations that lead to extensive organellar introgressions in the New World grapes.

1 - Jishou University, College of Biology and Environmental Sciences, Jishou, Hunan, 416000, China
2 - Smithsonian Institution, Botany, Department of Botany, National Museum of Natural History, Washington, DC, 20013-7012, USA
3 - Smithsonian Institution, Botany, Department of Botany, National Museum of Natural History, Washington, DC, 20013-7012, United States
4 - South China Botanical Garden, Herbarium, Guangzhou, Guangdong, 510650, China
5 - University Of Alaska Fairbanks, Herbarium (ALA) And Dept. Of Biology And Wildlife, University Of Alaska Fairbanks, 1962 Yukon Dr., Fairbanks, AK, 99775, United States
6 - Smithsonian NMNH, Botany, P.O. Box 37102, Smithsonian National Museum Of Natural History, Washington, DC, 20013, United States
7 - Smithsonian Institution, Department Of Botany, P.O. Box 7012, Washington, DC, 20013.0, United States

Keywords:
phylogenomics
grapes
Vitis
Vitaceae
introgressionj
discordance.

Presentation Type: Oral Paper
Session: PHYL2, Phylogenomics II
Location: Tucson F/Starr Pass
Date: Wednesday, July 31st, 2019
Time: 2:00 PM
Number: PHYL2003
Abstract ID:840
Candidate for Awards:None